二元羧酸半酯与环氧化合物反应动力学研究

用于印制电路板 ( PCB)的传统的热固化或光固化阻焊油墨是利用屏印的方法把图案印刷在覆铜板上 ,然后固化 .通过这种方法得到的图案不够精细 ,应用上也受到一定限制 .为此 ,近年来国际上研制出一类新型的阻焊油墨——碱液显影型阻焊油墨 [1～ 3] .它是通过曝光、显影及后固化等步骤形成精确的图案 ,可用于制备高密度的电路板 .通常 ,碱水显影型阻焊油墨由碱溶性光敏树脂 (组分 A)、环氧化合物 (组分 B)、光引发剂、热固化剂和稀释剂组成 .组分 A由二元羧酸与含有光聚合性双键的线性酚醛型环氧化合物通过半酯化反应得到 ,羧基的引入使其具…     

碱水显影阻焊油墨研究—羧基与环氧基的反应

二元酸单甲酯;环氧化合物;碱水显影阻焊油墨研究—羧基与环氧基的反应     

叔碳酸缩水甘油酯改性碱溶性酚醛环氧丙烯酸酯的研究

为了获得高分辨率和耐侧蚀性能优异的阻焊油墨，本文利用叔碳酸缩水甘油酯（E10p）对碱溶性酚醛环氧丙烯酸酯进行改性，并将其应用到阻焊油墨体系。实验结果表明，该改性树脂具有优异的感光性，同时涂层性能测试表明该树脂具有优异的耐热性及柔韧性。与未改性树脂相比，该树脂所制备的阻焊油墨分辨率由75 μm线距提高到50 μm，侧蚀由37.5 μm降低到24.5 μm，表现出了更高的分辨率及更优的耐侧蚀性。     

腰果酚缩水甘油醚改性碱溶性酚醛环氧丙烯酸酯的制备及应用

利用腰果酚缩水甘油醚与经酸酐酸化后的酚醛环氧丙烯酸酯反应,得到改性碱溶性酚醛环氧丙烯酸酯树脂,并将其应用到感光型阻焊油墨中。实验通过红外以及核磁氢谱证明了目标产物的成功合成。该改性树脂所制得的涂层具有优异的感光性、耐热性以及力学强度,同时柔韧性得到提升。将其应用到感光型阻焊油墨中,与用未改性碱溶性酚醛环氧丙烯酸酯树脂制得的油墨相比,在保持良好显影性和感光性的同时,解析度由140μm提高到了85μm,显影线条的最小侧蚀由37.1μm降低到10.4μm,展现了优异的抗蚀刻能力。     

羧基化环氧丙烯酸酯合成及在光成像阻焊油墨中的应用

树脂;多元羧酸酐;光固化;碱显影;羧基化环氧丙烯酸酯合成及在光成像阻焊油墨中的应用     

紫外线固化喷墨打印墨水的研究及应用进展

紫外线(Ultra Violet, UV)固化喷墨打印技术将打印技术与UV固化系统结合，集成了喷墨打印技术无接触、操作简单、低成本及UV固化后无溶剂残留、环保的特点，广泛应用于印制电路板中阻焊层的制备，陶瓷材料、盲文及电子器件的制备，纺织品制造，木材表面的修饰或保护等领域。UV固化喷墨打印墨水是该技术的关键原料，它主要由UV单体、UV预聚物、光引发剂、添加剂及助剂等组成，并根据不同应用要求添加功能材料，如金属、金属氧化物、碳纳米材料或量子点等。UV固化喷墨打印技术用于阻焊层制备时的关键在于墨水固化后形成的涂层与基材粘附力的调控，涂层与基材结合既要保证阻焊的效果，又要在阻焊后易于分离并去除。了解UV固化喷墨打印技术在应用中的各种关键因素及对策，对于其进一步推广应用具有重要意义。     

无铅焊膏研究进展

用无铅焊膏代替传统的Sn-Pb焊膏是近年来研究的热点。本文比较了Sn-Ag,Sn-Zn,Sn-B i系无铅焊料的优缺点并介绍了国内外对Sn-Ag,Sn-Zn,Sn-B i系无锅焊料研究所取得的研究成果,并详细阐述了助焊剂的分类以及主要活性成分的用途。     

功能助剂对触控屏UV防护油墨应用性能的影响

研究了功能助剂对触控屏UV防护油墨应用性能的影响,通过考察光引发剂、活性稀释剂、填料等对触控屏UV油墨制备、硬度测试、附着力测试、褪膜时间等应用性能的影响。结果表明,2,4,6-三甲基苯甲酰基-二苯基氧化膦(TPO)引发剂与油墨配方体系相容性优良,且反应活性很高可达优+级,可有效改善油墨的耐氢氟酸性能,且添加TPO的油墨稳定性好,耐黄变,安全环保无异味。将甲基丙烯酸羟乙酯(HEMA)与三羟甲基丙烷三丙烯酸酯(TMPTA)适量配比复配,可使UV防护油墨产品的粘度适中、固化速率加快、流平性好、表面硬度高、附着力高等。将用滑石粉与超细硫酸钡(BaSO_4)按一定比例混合制备防护油墨可有效提高油墨产品的耐氢氟酸能力及附着力。     

儿童的铅中毒问题──Ⅱ．彩色油墨中铅的测定

用能量色散Ｘ射线荧光分析法测定了某厂生产的４４种彩色油墨纸中的铅含量．结果发现，除５种油墨外，其它３９种彩色油墨纸中的铅含量均比对照纸中高９倍以上，其中桔黄色、桔红色树脂胶版油墨高５００倍以上，棕色树脂胶版油墨高３７９倍，深黄色和柠檬黄色树脂铅印油墨分别高１７０和１１３倍．这表明，彩色油墨印刷品可能是儿童慢性铅中毒的重要污染源．     

醇溶性聚氨酯凹印油墨的制备与性能研究

目的研制替代非环保、不安全的氯化聚丙烯类油墨的新型油墨。方法以醇溶性聚氨酯为油墨用连接料,通过添加分散剂、哑粉、钛白粉、溶剂等助剂,进行通用于PET薄膜、NY薄膜和BOPP薄膜的凹印油墨的制备试验,并对所制得油墨的颜色、着色力、细度、黏度、附着牢度、初干性、溶剂残留量和耐水煮等性能指标进行了测定和分析。结果该油墨不含苯类和酮类,且溶剂残留符合食品包装要求。结论该油墨是一种安全环保的通用型新型凹印油墨。     

High-speed microcontact printing

We have demonstrated microcontact printing (muCP) of self-assembled monolayers in the millisecond regime. The contact formation and separation of the stamp and substrate was studied with high-speed video recordings. Using high ink concentrations and contact times as short as 1 ms, we printed monolayers of hexadecanethiol on Au, which served as a selective etch resist. High-speed muCP yields defect-free monolayers that are independent of the dimensions of the printed patterns, have high contrast between printed and unprinted areas, and enable perfect reproducibility of prints.     

Reactive wetting, evolution of interfacial and bulk IMCs and their effect on mechanical properties of eutectic Sn-Cu solder alloy

Lead free solders are increasingly being used in electronic applications. Eutectic Sn-Cu solder alloy is one of the most favored lead free alloys used for soldering in electronic applications. It is inexpensive and principally used in wave soldering. Wetting of liquid solder on a substrate is a case of reactive wetting and is accompanied by the formation of intermetallic compounds (IMCs) at the interface. Wettability of Sn-0.7Cu solder on metallic substrates is significantly affected by the temperature and the type of flux. The wettability and microstructural evolution of IMCs at the Sn-0.7Cu solder/substrate interfaces are reviewed in the present paper. The reliability of solder joints in electronic packaging is controlled by the type and morphology of interfacial IMCs formed between Sn-0.7Cu solder and substrates. The formation and growth mechanisms of interfacial IMCs are highlighted. Mechanical behavior of bulk solder alloy and solder joint interfaces are analyzed. The characteristics of the IMCs which have marked effect on the mechanical properties and fracture behavior as well as reliability of solder joints of the alloy are discussed. An attempt has also been made to discuss the effect of cooling rate and strain rate on shear strength, tensile properties and creep resistance of the solder alloy. It is recommended that future work should focus on evolving a standard procedure involving sequential assessment of wetting behavior, evolution of IMCs and mechanical properties.     

A polypyrrole/polymethylene pattern on gold using a micro-contact printing technique

A micro-contact printing technique was used to fabricate a polypyrrole/polymethylene pattern on a gold surface. ω-(N-Pyrroyl)undecanethiol (PyC₁₁SH) acts as ink for the generation of a pyrrole-terminal monolayer patterned on gold. This monolayer-patterned surface functions as a resist for the selective growth of polymethylene by catalytic decomposition of diazomethane on the gold surface. It also functions as a monomer for the electrochemical polymerization of pyrrole on the PyC₁₁SH monolayer-patterned surface. The polypyrrole/polymethylene pattern was fabricated by an electrochemical polymerization method. The polypyrrole was grown on the pyrrole-patterned surface by potential scanning between 0.0 and 1.2 V vs. Ag wire. The thickness of the polypyrrole growth increases with the increasing number of cycles. The structural features of the patterned surface can be determined by scanning electron microscopy and atomic force microscopy. Electronic Publication     

Sn-Pb-RE钎料的塑性变形抗力研究

利用拉伸实验方法研究了室温下Ｓｎ－Ｐｂ－ＲＥ钎料的塑性变形抗力。钎料的变形抗力随稀土含量的增加而提高。稀土垢加入使钎料组织均匀细化，导致位垒硬化和多滑移硬化作用增强。同时，稀土存在晶界偏聚，牵制了晶界的运动，因此提高了钎料的变形抗力。     

Differentiation and dating of red ink entries of seals on documents by HPLC and GC/MS

A novel approach for differentiation and dating of red ink entries of seals on documents was developed based on ion‐pairing HPLC (IP‐HPLC) and GC/MS. Sixty‐nine red ink pastes of seals were collected and the chromatographic conditions for separation of the dye components by IP‐HPLC and the volatile additives by GC/MS in the ink entries were optimized. According to the dye components and additives, the ink entries were classified by HPLC with a multi‐wavelength UV detector. The volatile components of the inks were identified by GC/MS and the classification of the ink entries was also investigated based on these volatile additives. The results showed that most of the ink entries of the seals can be differentiated by combining HPLC with a multi‐wavelength detector and GC/MS methods. The degradation of the standard dye mixtures and the compositional changes of the ink entries of seals were investigated in light or natural aging conditions. The results indicated that the dye components decomposed in light or natural storage conditions, while the rates of the degradation depended on the structures of the dye components, the aging conditions, even the additives of the ink pastes. The results also showed that there existed good relationships between the compositional changes of the ink entries and the aging time, which can provide scientific evidences and valuable clues for dating of the ink entries.     

大面积功率器件软钎料的焊接失效分析

针对大面积功率器件软钎料的失效问题,运用扫描电子显微镜(SEM)分析了SnPb软钎料的微观结构并运用能谱仪对其进行成分分析,找出了失效的主要原因:对软钎料进行刚玉抛光后,未能将残留在软钎料内的Al2O3成分完全去除,以至于器件的可焊性变差.根据分析提出了改进意见,较好地解决了SnPb软钎料的失效问题.     

DATINK pilot study: An effective methodology for ballpoint pen ink dating in questioned documents

Establishing the approximate age of an ink entry from a questioned document is often a complicated task and a controversial issue in forensic sciences. Among the existing approaches, the analysis of solvents in ballpoint inks may be a useful parameter for determining the age of ink on paper. In recent years, several ink dating methods have been proposed. These methods have been based on the analysis of common ink solvents using gas chromatography/mass spectrometry (GC/MS) as the analytical platform. Despite these recent methods, several questions remain. The aim of this work was to develop an ink dating methodology (DATINK) for documents written by ballpoint pens based on the disappearance of volatile solvents from the ink entry. Multiple solid-phase microextraction (MHS-SPME) coupled to GC/MS was used to measure the solvents from ink entries made with four BIC^® ballpoint pens. The β parameter, the remaining fraction of the analyte in the system after one equilibration, corresponding to the successive extractions was considered for modelling a mathematical equation for later ink age dating. Preliminary tests of DATINK method showed that it was possible to detect the presence of ink solvents on documents up to the studied five years. The analyses of different real samples of known age were analyzed in terms of β values, which provided a mean relative error of 21%. The proposed use of β parameter for estimating the absolute age of ballpoint ink entries has shown promising results with a standard deviation of β ranging from 0.002 to 0.004.     

镧对Cu_6Sn_5长大驱动力及焊点可靠性的影响

在Sn60 Pb40钎料合金中加入微量稀土元素镧可以抑制表面组装焊点界面处Cu6 Sn5金属间化合物的生长 ,进而使焊点热疲劳寿命提高两倍。基于扩散动力学的热力学计算结果表明 ,添加微量稀土元素镧可降低Cu6 Sn5金属间化合物的长大驱动力 ,但存在一个镧的有效局部摩尔分数范围 ,0 18%是其极限值 ,0 0 8%是其最佳值。